Safety hoist mechanism for loading skips



July 9, 1929. E. H. LICHTENBERG SAFETY HOIST MECHANISM FOR LOADING SKIPSFiled Feb. 10, 1923 6 Sheets-Sheet ii /Wars;

y 9, 1929- E. H. LICHTENBERG 1.720.048

SAFETY HOIST MECHANISM FOR LOADING SKIPS Filed Feb. 10, 1923 6Sheets-Sheet 2 Wdinbeg y 9, 1929- E. H. LICHTENBERG 1.720.048

SAFETY HOIST MECHANISM FOR LOADING SKIPS Filed Feb. 10, 1925 6Sheets-Sheet 5 GER)? ear July 9, 1929.

E. H. LICHTENBERG Filed Feb. 10, 1923 Jll 6 SheetsSheet y 9, 1929. E. H.LICHTEN'BERG 1. 2 .0

SAFETY HOIST MECHANISM FOR LOADING SKIPS Filed Feb. 10, 1923 6 t 5h 5ZHlidoZenez-y y 1929- E. H. LICHTENBERG 1.720.048

SAFETY HOIST MECHANISM FOR LOADING SKIPS Filed Feb. 10, 1923 6Sheets-Sheet 6 gnuenifoz Patented July 9, 1929.

UNITED STATES- PATENT OFFICE.

ERICK H. LICH'I'ENBERG, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO KOEHRINGCOM- PANY, 0F MILWAUKEE, WISCONSIN, A CORPORATION.

SAFETY HOIST MECHANISM FOR LOADING SKIPS.

Application filed February 10, 1923. Serial No. 618,369.

Street or road pavers of the class disclosed by my Letters Patent No.1,141,470, issued June 1, 1915, are being constructed in extremely largesizes today as compared with those manufactured at the time of myapplication for the above patent. To exemplify, the capacity of themixing machines forming a part of, said pavers is in many instances asmuch as thirty two cubic feet, and the loading skip which feeds thebatch of concrete aggregates to the mixer-is called upon to raise hugeloads from the ground and dump them into said mixer. These loadscommonly exceed 6,500 pounds of aggregates, and the skips themselves arebuilt as large as twelve feet in width.

The problem of operating the loading skip in a large machine of theclass referred to, is no mean one, having in view the factors of safetyand efficiency ofvmovement. In other words the skip must be raisedquickly, and must be brought to a stop at the ex tremes of its movementsquickly, forfmost efficient action; and at the same time the danger offalling of the skip accidentally thru breakage of any cables must beavoided.

I attain the objects above mentioned, and certain other objects thatwill be understood upon perusal of the following specification, byutilizing one or more of the following important provisions ofconstruction:

' In the first place, I employ a double hoisting cable running from ahoisting shaft to the loading skip for elevating the latter in operationof the shaft. Since the skip handles tremendous loads affording it atremendous leverage should it move even slightly laterally when lifting,there would be liability of serious damage and improper operation if thelifting or hoisting cables for the skip do not act thereon with equaltension or-pull while raising the skip and lowering it. This phase ofaction has created the problem of supplying an equalizing device to acton said hoisting cables connected with the skip to equalize theirtension for the purpose described. The method of arranging, andoperating the cables, and equalizing their tension when acting on theskip in raising or lowering movements of the latter, is consequently animportant feature of this invention, and as presented hereinafter, ithas proved in service of exceptional advantage and practicability.

The double cable raising means for the skip has the additional functionof affording safety in providing two different elevating contrivances,the failure of one of which would not result in accidental dropping of{life skip and consequent damage or loss of In the machine of myinvention, the skip hoisting cables themselves connect with an auxiliaryhoisting shaft which is operated from a main hoisting shaft somewhatafter the manner which is presented in my Letters Patent No. 1,103,788,of July 14, 1914, and Letters Patent-No. 1,107,171, of August 11, 1914,which illustrate machines of much smaller construction than those now inuse. From the auxiliary hoisting shaft which carries a large diametercable drum, there leads a main hoisting cable to the main hoist shaft.Should this cable be broken ordinarily, if no provision is made againstthe same, the skip will drop instantly with or without its load,according to the conditions. To provide against this, there is utilizeda safety brake or device which enters vinto combination in its action,with the control means for the auxiliary hoisting cables that connectwith the skip direct, so that there are controls on the safety brake ordevice, and the auxiliary hoisting cable mechanism for the skip whichare operable from a common control means.

Additionally, this invention includes certain contrivances whichregulate the action of the main ho ist'shaft to brake its operation asthe skip reaches its extremes of movement, thereby facilitating theproper acceleration of movement of the skip when necessary, for highefficiency of operation, and yet enabling the skip to be stopped quicklywithout any tendency of the main hoist cable being caused to over-run onits drum, as would otherwise occur. The special brake devices employedforthe last mentioned purpose likewise enter into peculiar combinativeaction with the general control mechanism. I I

The invention additionally involves an independent emergency control forthe main hoist shaft, which in this instance forms a part of the safetybrake or control device, and is desirable in the operation of themachine.

Included in the invention are other specificfeatures of construction,and for a full understanding of everything appertaining to theinvention, reference is to be had to the following description, andaccompanying especially the control devices which are intended to beillustrated primarily.

Figure 3 is a rear view showing certain of the mechanism illustrated inFig. 1, as when looking from the rear end of the machine, the skip beingomitted, but the hoisting cables being shown at least in part, as wellas a number of the control connections.

Figure 4 is'a perspective view showing more particularly the selectormechanism utilized for controlling the action of the brakes affectingthe operation of the main hoist drum, the operation of the main skiphoist clutch, and certain other connected features of the mechanism.

Figure 5- is a side view partially broken away, of the safety brake andclutch means,

the safety brake being one which is auto= matio in its operation whenits safety function comes into play, the auxiliary skip hoist shaftbeing shown in section.

Figure 6 is a vertical section view thru the features of constructionshown in Fig. 5.

Fi ure 7 is a dia rammatic lan view of the auxiliary hoist shaft, itscable drums, guiding sheaves associated therewith, and

. thecables leading from the drums with the equalizing feature whichembodies a construction applied to the under side of the skip, whichskip is not illustrated.

Figure 8 is a slightly enlarged view showing the method of trainingtheskip raising cables about the guiding means on the skip and about theequalizer also carried by the skip. V

Figure 9 is a fragmentary view of a portion of the skip looking towardone of the cableguides, as when viewing the skip in side elevation.

Figure 10 is a view in elevation of one of the cable guides carried bythe skip, and the cables being shown in proper relation thereto.

Figure 11 is a rear edge view of the parts shown in Fig. 10. p

F igure 12 is an end edge view of the parts shown in Fig. 10. I

Figure 18 is a sectional view showing in plan the equalizer and methodof training the cables thereabout.

Figure 14 is an edge view of the parts shown in Fig. 13.

Figure 15 is a-perspective view showing more particularly the brakedevices co-operating with the main hoist shaft brake drum and hoistdrum, with the controlling parts actuated from the skip in properrelations to other parts.

Fig. 16 is a somewhat diagrammatic, elevational View of the skipknock-out for the main hoist clutch.

General construction of machine.

The general construct-ion of my machine will first be set forth. r

' A mixer A is mounted on the base frame B of the machine in anysuitable manner, and as illustrated, the construction of my pavingmachine is that commonly known as the Koehring paver. The base frame Bcarries a superstructure frame C, in uprights of which is suitablyjournaled the auxiliary skip hoist shaft 1, seen best in Fig.1 3.. Theshaft 1 carries the operating drum 2 of large diameter, and the skiphoisting drums 3 and 3 of small diameters, the drums 3 and 3are'provided, extending from their ends toward the central portions oftheir peripheries, ,with opposing spiral grooves, each groove adapted tohave wound therein an end portion of a skip hoist cable, of which thereare two designated 4 and 5. The skip hoist cables after'being firstwound at their ends a couple of times around the drums 3 and 3, leadover guiding sheaves 6, shown only in Fig. 7, same being carried by anupper extremity of the superstructure frame C, and from these downwardbeneath the skip 7 around which they are guided and connected bysuitable members 8, and equalized by an equalizer lever 9 to be laterset forth in detail. From the operating drum 2 upon the auxiliary shaft1, there leads a main hoist cable 10' which is received by and windsabout the main hoist drum 11 on the main hoist shaft 12, suitablyjournaled on the base frame B, and driven by a, suitable motor carriedon said frame in any well known manner. The same motor is adaptedtodrive the mixer A, and as seen somewhat generally in 2, there aredriving connections which lead to the traction mechanism of the machinethru variable speed gearing.

While the mixer A is in operation, under the control of a main lever 13,a main hoist clutch 14 on the shaft 12 is adapted to operatively connectsaid shaft for driving the drum 11, which is otherwise loose thereon.This driving action is adapted to wind and unwind relatively to thedrum, the main hoist cable 10. Vhen wound on the drum 11 the cable 10actuates the operating drum 2, and thereby the shaft 1,to raise the skip7 thru the winding-up action of the cables 4; and 5, in relation to thedrums 3. U winding of the cable 19 from the drum 11, causes a reverseoperation which is obvious.

On the shaft l is the safety device which involves a safety brake and asafety clutch that will be more fully described hereinafter, in itsproper place.

It is notable that as the skip 7 is raised, and when it assumes itsupward extreme of elevation wherein it charges the mixer A, a knock-outdevice consisting of a yoke 15 connected with the pivot bracket 7 of theskip 7, will have acted thru a rod 16 near the inclined brace 17 of thesuperstructure C, to release the clutch 14, and thereby di's continuethe hoisting operation of the skip, at the same time applying a brake tohold the skip in its elevated position, as will later be set forth. Therod 16, as shown in Fig. 1, extends along the brace 17, passes thru anarm 18 on the shaft 19 which carries the clutch yoke 20 of said clutch1 1. The lower end of the rod 16 has a head or abutment 16 adapted toengage the arm 18 to shift it for rocking the shaft 19 to throw theclutch 14 out as the said skip '7 reaches its upward limit of movement.A spring 21 tends to hold the arm 18 in a position maintaining theclutch yoke 20 and its clutch 14 disengaged, or with the driving act-ionof the motor discontinued in relation to the main hoist drum 11.

\Vithout at present going into the detail construction of the safety oremergency brake, generally designated D in Fig. 3, and elsewhere in thedrawings, it is notable that said device includes a brake drum 22 looseon the shaft 1, and about which a brake band 23 passes, the latter beingapplied continuously and automatically by means to be'described, andalso released from the drum 22 by lever 13, or both applied andreleased, by the emergency lever 24 (see Figs. 1 and 3) located withineasy reach of the'operator.

Normally there is a weighted lever 25 connected with said brake band 23to hold the brake band in active relation to the drum to insure thecontinuous and automatic ap-- plication of the brake 23 and thereby thesafety function of the safety device. The weight on the lever 25 isdesignated 26.

Under the above conditions it will be evident that assuming the mainhoist drum 1.1 to be released from the clutch and free from the actionof a local .or immediately co-operating brake, the lowering of the skip7 may ordinarily be controlled manually thru the brake band 23, operatedby the lever 13 acting thru connections to the brake 23, drum 22 andparts clutching the latter to shaft 1, as hereinafter described.Likewise supposing the skip 7 to be elevated at any point in its travel,it may be held at such an elevation independently thru a downwardmovement of the emergency lever 24. In fact the skip may be lockedagainst raising or the possibility of accidental lowering by turning alocking cam lever 27, pivoted to one of the uprights of thesuperstructure C, said lever 27 being adapted to be thrown from theposition of Fig. 1, leftward to engage its cam positively with the upperside of the lever 24 and stress lever 21 in the direction for applyingbrake band 23.

Thus far I have described the main features of my machine involving themixer, the charging skip, the raising and lowering means for the latter,and the automatic knock-out device for the clutch that stops the skip atits upper limit of movement, which broadly are provisions already knownin the art. Additionally, I have described that operation of the safetyor emergency brake and clutch means that acts as an auxiliary manualcontrol means for the lowering of the skip 7, and also as a brake tohold the skip raised at any desired elevation inde-' pendently of thehoisting drum.

Double cable skip hoist means.

Referring again to the drums 3 and 3, and the cables 4 and 5, it isnotable that the two cables 4 and 5 when extended from the drums intoconnection with the bottom portion of the skip 7, have a sort of Ushaped arrangement in top plan. The two cables 1 and 5 have their endswinding about the drums 3 and 3* from the bottom upwardly, so to speak,and in the same direction. Thus the cables wind upon the drumssimultaneously and with a corresponding pull at both ends of each cableas it freely moves over the sheaves 6. The same phase of actionreversely applies as the cables unwind from the drums.

It being almost a physical impossibility to so connegt cables with drumsas to maintain exactly the same tension on each cable if it bepermanently connected between its ends with a part to be actuatedthereby, and this problem being difiicult when a single cable having atwo end pull is used, it is obviously doubly difficult when two cablesare connected to the same object and a two end pull for each cable isutilized. It is under the above conditions that I have availed of theequalizing arrangement of the cables, and theequalizing, guiding, andcontrolling devices illustrated in Figures 7 to 14 inclusive, and whichwill now be set forth.

The guide members 8 each comprise a casting having tubular guideelements 8 and 8", which viewed from above and at the innermost portionof the guide member, are in different vertical planes and the samehorizontal plane, but which by reason of the peculiar curvature thereofin lateral directions, have their rear portions in the same verticalplane, but different horizontal planes. The equalizing member 9, seeFigs. 13 and14, is really a pivoted guide block having round endportions and pivoted on a short vertical axle 9 fixed to the under sideof the skip 7. The skip ,7, as seen in Fig. 9, has an angle ironsupporting flange or rest 28 on its under side which forms a clearanceway in which the members 8 and 9 are theskip are the end guide members 8and at a middle point beneath the skip is located the equalizing member9. The cable 4 leads oif from beneath the drum 3 over one of the sheaves6, down thru the guideway 8 of the end guide member 8, to and thru aguide groove 9* at the rear opposite portion of the equalizer 9, andaround a guide lug 9 of the equalizer, being thus crossed with the cable5 adjacent thereto. Thence the cable 4 passes to and thru a guideway 8*of the second end guide member-'8, then to and thru the guideway 8 ofsaid other opposite member 8, over the inside sheave 6 adjacent to thedrum 3, and around and attached to said drum 3. The cable 5 leads fromthe drum 3 over the inside sheave 6 adjacent to the drum 3, to and thruthe guideways S and 8 of the guide member 8 in alinement with the drum 3and sheaves 6 adjacent said drum. From the said guide member 8 the cable5 leads to and thru the inner guide groove 9" of the equalizer 9,crosses the cable 4 and passes to and t-hru the other guideway 9 of theequalizer, thence to the guideway 8 of the right handguide member 8 ofFig. 7 to and thru the gnideway 8 thereof, over the outside sheave 6nearer the drum 3 and around and attached to said drum 3 With the abovearrangement there is practically no movement of the cables 4 and 5relative to the skip when the heaviest load is upon the cables, namelywhen the skip is filled and being raised. Any slight variation in thetension of the cables becomes equalized as regards the pull of thecables transmitted to the skip, by rocking of the member 9. v

OOWWOZ mechanism for ship operations.

Referring primarily to Figures 1 to 4 inclusive, it is notable that themain control lever 13 is connected by a rod 30 with one arm of a bellcrank lever 31. The other arm of the lever 31 is connected by a rod 32leading to superposed selector arms 33 and 34 having curving or arcuateslots thereon. The rod 32 has a T shaped head32, the upper extension ofwhich enters the slot of arm 33, and the lower extension of which entersthe slot of the arm 34. The arm 34 is connected with a vertical shaft 35by being keyed or otherwise secured thereto, and the arm 33 is connectedto move a sleeve 36 loose on the shaft 35 and having an arm 37 The arm37 is connected. by a rod 38 to a bell crank lever 39, see Fig. 3, andconnected by a rod 40 to the emergency or safety brake band 23.

The shaft 35 is equipped with an arm 41,

see Figs. 1,3,. and. 4. The arm 41 isconnected by a rod 42 to an arm 43which is rigid on the shaft 19 previously mentioned as having the clutchyoke that :enables the clutch 14 to be thrown in and out forcommunicating the drive from the motor to the main hoisting drum 11. Theconnections of th'e'arm 34 and shaft 35 thru the rod 42 to the arm 43 onthe shaft 19, are best seen in Figs. 3 and 4, and'Fig. 15. 1

There are two brake bands 45'and 45 cooperative with a brake ell-1111145on thehoisting drum shaft 12, connected with the hoisting drum 11.

ward movement, and also when it reaches the extreme of its loweringmovement,

whereby to prevcnt'overrunning action of said brake drum that wouldotherwise cause the cable 10 to overrun and become unduly slack,sonietl'iing to be avoided for obvious reasons. The operation-of thebrake bands 45 and 45 is effected peculiarly under the control of theshaft 35 and the sleeve 36. Referring particularly to Fig. 15, it willbe noted that when the shaft 35 is rocked to move the clutch arm 43, seeFigs. 3 and 4, the shaft 13) is of course rocked. Figure 15 shows thatthe brake. bands 45 and 45 have connected thereto, brake levers54pivoted at 55 to the frame work. The levers54 auto matically act toapply their brake bands thru the provision of weights 54 on saidlevers.The operation of throwing in the clutch 14, by the arm 20 actuatedbyrocking of the arm 43, rocks the shaft'19 so as to cause an arm 44thereon to act thru a connection 44' to rock upwards a cam50 whichengages beneath the freeen ds of thelevers 54 whereby to raise saidlevers and their weights 54 in such a. manner asto release the drum 45from the brake bands 45 and 45. As previously deseribed,-when the skip.

7 reaches its upper limit of movement, the parts 16 and arm 18co-operate to disengage the clutch 14 by rocking movement of the shaft19 reverse to that previously set forth, such reverse rocking of theshaft 19 of course disengages the cam 50 from beneath the free ends ofthe levers 54, but it is to 'be noted that the skip 7 has connected toits pivot bracket 7 a connection composed of links and the small yoke 70which receives the free end portion of the outcr brake band lever 54,and said lever is upheld while the skip is upraised so that its brakeband 45 does not act upon the drum 45'. On the other hand, however,disengagement of the cam 50 as just described, permits the other innerlever 54 to lower under the action of its weight 54, thereby. applyingthe brake band 45 to the drum 45, as the clutch 14 is These brake bands45 and 45" constitute braking: devices to retard and brake the turningor rotation of the drum 11' ates the rod 47 and a bell crank 48 tothereby lift a vertical lift bar 49, the upper end of which will engagethe inner brake band lever 54 to raise it to free drum 45, while theskip is lowering under the control of the reverse movement of the lever13. This action renders inactive the brake band 45 which was renderedeffective for braking the drum 45' when the skip reached its upper limitof movement. The inner brake band lever 54 1s thus held elevated duringlowering movement of the skip. Of course, asthe skip lowers, theconnection comprising the links and yokes 7 0*" gradually moves downwarduntil the outer lever 54 which co-operates with the brake band 45 islowered sufiiciently as the skip reaches the lower limit of itsmovement, to enable the brake band 45 to act on the drum 45. In thisway, and automatically, the skip causes a braking action on the drum 45,thru the brake band 45, to prevent overrunning of the cable 10relatively to the drum 11, as the skip comes to a stop at its lowerextreme of movement.

Summarizing this whole detailed action, it is noted that on upwardmovement of the skip 7 on engaging the clutch 14, cam 50 is disengagedfrom the levers 54. The outer lever 54 is held up by the connection 7 0,the inner lever 54 is permitted to drop and actuate its brake band 45 tobrake the movement of the drum 11. Then when the clutch 14 is thrown outand the skip 7 caused to lower, such action thru thelift bar 49 raisesthe previously active inner lever 54, rendering inactive its brake band45, and when the skip gets to its lower stopping position, the outerlever 54 will have moved downwardly sufficiently for the application ofits brake band- 45 to the drum 45. In this way, in brief, do the leversand brake band co-operating with the drum 45, act to prevent overrunningof the cable 10 relatively to the drum 11.

The emergency brake on safety device.

This means D, best shown in Figs. 5 and 6, includes the described brakedrum 22, with its coacting band 23, and certain internal contrivances.Drum 22 is loose on the shaft 1, and has an adjacent disk 60 that may besaid to close the drum at one side. Disk 60 is keyed to the shaft 1 andcarries a series of dogs 62 to engage notches 61 provided internally ofthe drum 22. The drum 22 has a hub extension 22 on which are mounted thefriction members 63 and 64, between which is the dog operating frictionring 65, having an arm 66. The arms 66 receive rods 67 each socketed atone end on a dog 62, and encircled by a s ring 68. Bolt head lugs 69 areprovided or the ring 63 to fix the latter relative to the drum 22. Theshaft 1 is rotated clockwise as the skip 7 is elevated to charge themixer, and at the same time the drum 22 is held stationary by its brakeband 23, tho the disk 60 turns with the shaft 1, of course, carryingdogs 62 with it. As the drum 22 carries the rings 63, 64, and 65, andthe last is connected to dogs 62, the turning of thedisk 60 with thedogs is such that a pull is exerted on the dogs through parts 67 and 65,and the dogs stay free of the notches 61. If the cable 10 should breakthe disk 60 would reverse its above movement and the pull on the dogs 62being relieved, they enga e the notches 61, and since the drum 22 is eldstationary by the band 23, the skip cannot fall.

The action of the dogs 62 to engage the drum 22 always takes place whenthe machine is operated to lower the skip. On this account, if the skipis to be lowered under control, the'brake band 23 must be released fromthe drum 22, and this is done manually by the lever 13 usually, and inemergencies the operation will be performed manually when desired byaction of themanual lever 24 previously described.

So long as the lever 25 is lifted, as may be caused thru the connection40, the skip may lower under control, the weight 26 tho will restore thebrake action of the band 23 instantly when necessary.

General operation of machine.

in the position of Fig. 1, namely at neutral.-

The-lever 13 is thrown to the right in Fig. 1 for engaging the clutch 14with the hoisting drum 11 to drive the latter to wind up the cable 10thereon, turn the operating drum 2 clockwise with the drums 3 and 3,

wind up the hoisting cables 4 and 5, and thus raise the skip 7. Whilethe skip is being raised, the drum 22 is stationary and the disk 60 isbeing turned clockwise, rotating 7 within the drum 22, as previously setforth.

'The action of the control mechanism for the clutch 14 and the brakeparts which coact with the drum 11, is substantially as follows: Themovement of the lever to the right causes a movement of the rod 32,forcing the selector arm 34 clockwise with the shaft 35, see Figs. 3 and4, and selector arm 33 remains quiescent. The movement of the arm 34actuates the rod 42 and renders active or throws in the clutch 14 tostart the turning of the hoisting drum 11 in the operadisk 60keyedto'the shaft 1.

tion of lifting theskip above set forth. 'Simultaneously with thethrowing of the clutch 14 into action, the rocking of the shaft 1S)v bywhich the clutch is moved, lifts the cam 50, see Fig. 3, which acts onand liftsthe 4 ulled .t-o trio the arm 18 U'YWtLlClS rockin l l 7 tn theclutch shipper shaft 19 so as to throw out the clutch 14E, whereupon theskip stops and is held from moving downwards by means of the brake band.23, acting on the shaft 1 thru the drum 22, the dogs 62, and the skipreaches its uppermost position, the brake band 45 is applied to the drum45' on the main hoistsha-ft 12, to thereby brake the turning of the drum11, arresting move- 'ment of the latter and preventing any tendencyofsaid. drum to continue movement thru its inertia of previous operation.The result of such undesired turning movement .would be to unwind thecable lO unduly,

Creating slack that would interfere with the eflicient operation of themachine.- I'Vhen it is desired to lower the skip, the control levervv 13ismoved. to the'left across its neutral point -..or;1.'eversely to thedirection previously. mentioned, and this imparts an oppositemovementwhich causes lowering of the skip,

the leftward movement of the lever 13 actuating the selector arm 33 thistime and the sleeve 36. The rod 38 is thus operated, and its movement'istransmitted-to the love and other parts atv the upper portion of F1 1,which controlthe release ofthe brakehand 23fromthe drum-22. The rod 38vof course s-actuates the rod, &0 and arm 40 to the above end, and therelease of the tension of the safety brake band 23obviously permits thedrum 22 to turn in a contraclockmse direction, actuated by the dogs 62and-the disk :60, under the influence of the pulls of the cables tandfiwhich are then imwindingfrom the drums 3 ant 3 in the skip loweringmovement. The skip can be instantly stopped at any point in suchlowering move- ;ment. The action of the selector arm 33 and other partsjust described, under influence of the leftward movement of the lever13, not only releases the brake band 23, but also operates the crank 48thru the rod 4'47,

: "and thereby raises the lifting member or rod 49. so as to release thebrake band acting on thedrum 45f, removing the braking. ac-

tion of this member from the drum 15, and permitting thehoisting drum 11to turn inci-. dent to. the unwinding of the cable 10 there- Also as thei from. As the skip goes down the linkage 70 will automatically lower,gradually cause ing application of thebrake hand 45 to the drum -15, andthereby tothe drum-11, so that as the skip reaches its lower limit ofmovement the drum 11 will again be braked, so to speak, and preventedfromv overrunning by reason of the inertia of its cable unwindingmovement, causing the cable to unwind more than necessary.

It will be noted on reference to Fig. i, that the arm 34 is providedwith a hook member 34? and that the rod 32 has a hook 32".. The purposeof these provisions is as follows: In the event it is desired to stopthe skip 7 in its upward travel before the regular knockout actioncaused by the rod 16 acting on the arm 18, theoperator may'throw the.lever to the left, or in other words restore. it to, its central neutralposition. This will. cause the hook 32 to engage the hook mean. her 34and throw the arm 34 into its normal or original position. This willcause a release action of the clutch 1 1i Simiiltaneously, of course,the safety hrake 23. will hold the skip elevated and subject to further1aising movement if the lever 13 is again thrown to the right, orsubject to be lowered under the control of either thelever 13 thrown tothe left of its neutral position, or the lever 2% which always givesimmediate manual control. r V

Also in-theabove action cam 50 will lower allowing brakes 45 and a5- tostop the cable from further unwinding. i

What I claim is: r

1. In concrete mixer loading mechanism of the :class described, incombination, a loading skip, hoisting means therefor including aplurality of cables independently connected with the skip, and means foropcrating both cables with equalized forces for elevating the skipincluding cableequaliz ing devices on the skip.

2. In loading mechanism of the class described, in combination, aloading skip, hoisting means therefor including a pluralityof cablesindependently connected with the skip, so that if one' cable breaks "theother will hold, winding means for the ca bios to act thereonsimultaneously to raise and lower the skip, and an equalizing device;

carried by the skip and common. to both cables to equalize their action.on the skip in actuation of the latter. v

3. In loading mechanism, the combination of a loading skip, hoistingmeans therefor including separate cables extending downward to one sideof theskip, across the skip, and upward at its other side, andvconnected with the skip so that in the event of breakage of one cablethe-other cable will hold, a winding mechanism common to both cables foractuation thereof, and an equali-a ing member on the skip cooperativewith 1139 Iii both cables for equalizing the forces transmitted to theskip through the cables from the winding mechanism.

connection with and extending transversely beneath tlio'skip, means foractuating the cables, and means for equalizing the effective forcestransmitted to the skip from said cables I 5. In loading mechanism, thecombination of a skip, hoisting means for the skip including a hoistingshaft, winding drums upon said shaft, a pair of cables adaptedsimultaneously to wind on and unwind from said drums and havingengagement with the skip, and an equalizing device on the skip engagingthe cables whereby equal operating forces of both cables may at the sametime be transmitted to the skip, the cables extending crosswise of theskip beneath the same and leading to the winding (lILlll'lS fromopposite sides of the skip.

(3. In loading mechanism, the combination of a skip, hoisting means forthe skip including a hoisting shaft, winding drums upon said shaft, apair of cables adapted to wind on and unwind from said drums and havingengagement with the skip, whereby equal operating forces of both cablesmay at the same time be transmitted to the skip,

the said cables being arranged in substantially parallel relations asregards the elements thereof, said cables extending downwardly from onedrum beneath the skip and then up to the other drum, and an equalizingdevice intermediate and common. to the ca bles.

7. In loading mechanism of the class described, the combination of askip, hoisting means therefor including a pair of cables, a hoistingshaft, drums on said hoisting shaft, each drum having the ends of saidcables winding thereabout and each cable winding from an end of the drumtoward its middle portion, the cables intermediate their ends beingengaged with the skip, a rocking equalizing member pivoted to the skipand having the cables engaging the same from opposite sides thereof, andguiding means on the skip for controlling the engagement of the cablestherewith.

8. In loading mechanism of the class described, the combination of askip, pivoted at one end, hoisting means therefor for raising its otherend including a pair of cables, a hoisting shaft, drums on said hoistingshaft, each drum having the ends of said cables winding so as to wrapthereabout in opposite directions namely, from the drum ends toward itsmiddle, the cables intermediate their ends passing beneath the skip, a

rocking equalizing member pivoted to the skip andhaving the cablesengaging the same from opposite sides thereof, and guiding means on theskip for controlling the engagement of the cables therewith. said rockng member and guiding means so coacting with the cables as to permitrelative slippage. of the same and the skip.

9. In loading mechanism of the class described, the combination of askip, hoisting means therefor including a pair of cables, a hoistingshaft, drums on said hoisting shaft, each drum having the ends of saidcables winding thereabout, the cables intermediate their ends beingengaged with the skip, a rocking equalizing'member pivoted to the skipand having the cables engaging the same from opposite sides thereof, andguiding means on the skip for controlling the engagement of the cablestherewith.

10. In a machine of. the class described, the combination of a loadingskip, means for raising said skip including a main hoisting drum, anauxiliary hoisting shaft, an operating drum on t e auxiliary shaft,cable means connecting the latter to the skip, other cable meansconnecting the operating drum with the main hoisting drum, control meansfor the main hoisting drum to clutch same to a driving element to raisethe skip and unclutch it to stop the skip raising movement, brake meanscoacting with the auxiliary shaft in lowering the skip or holding itraised, and other brake means to coact with the main hoisting drum toapply brake forces thereto when the skip is stopped at its upper limitof movement, and stopped at its lower limit of movement.

11. In a machine of the class described, the combination of a loadingskip, a main hoisting shaft and hoisting drum operated thereby, anauxiliary hoisting shaft, cable means connecting said auxiliary shaftwith the main hoisting drum, auxiliary hoisting cable means connectingthe auxiliary shaft and the skip, main control means for driving thehoisting drum from the drive shaft, brake means to coact with theauxiliary shaft and releasable to permit it to lower the skip, andautomatic safety clutch means coacting with the auxiliary shaft toprevent dropping of the skip if the cable means between the hois tshafts breaks while said brake means is released during upward orlowering movements of the skip.

12. In a machine of the class described, the combination of a loadingskip, a main hoisting shaft and hoisting drum operated thereby, anauxiliary hoisting shaft, cable means connecting said auxiliary shaftwith the main hoisting drum, auxiliary hoisting cable means connectingthe auxiliary shaft and the skip, main control means for initiatingdriving of the hoisting drum from the drive shaft, safety control meansfor preventing lowering ofthe skip in the event of breakage of the cableconnection between the hoisting drum and auxiliary hoisting shaft, andoperative connections between the safety control means and the mainoperating means whereby the former may be controlled from the latter.

13. In a machine of the class described, the combination of a loadingskip, a main hoisting shaft and hoisting drum operated thereby, anauxiliary hoisting shaft, cable means connecting said auxiliary shaftwith the main hoisting drum, auxiliary hoisting cable means connectingthe auxiliary shaft andthe skip, main control means for drivin thehoisting drum from the drive'shaft, satety' control means for preventinglowering of the skip in the event of breakage of the cable connectionbetween the hoisting drum and auxiliary hoisting shaft, theauxiliarycable means including a pair of cables between the auxiliaryshaft and the skip, with means tocreate equalization of the liftingeffects thereof on the skip, so that if either cable breaks the otherWill be effective 3 to prevent dropping of the skip and for temporaryuse to operate the skip.

In testimony whereof I affix my signature.

ERIGH H. LICHTENBERG.

